$\sum\limits_{j=0}^{1 }{{(2j-4)}}=$
Answer: What is the question asking for? $\sum$ tells us to find the sum. The question is asking for the sum of the values of $2j-4$ from $j = 0$ to $j = 1$. Evaluating $\begin{aligned} \sum\limits_{j=0}^{1 }{({2j-4})}&= (2(0)-4) + (2(1)-4) \\\\ &= -4 + (-2) \\\\ &= -6\end{aligned}$ The answer $\sum\limits_{j=0}^{1 }{({2j-4})}=-6$